The invention relates to a superconducting structure comprising a plurality of coated conductor tapes, each with a substrate which is one-sided coated with a superconducting film, in particular an YBCO film,
wherein the superconducting structure provides a superconducting current path along an extension direction (z) of the superconducting structure,
wherein the coated conductor tapes provide electrically parallel partial superconducting current paths in the extension direction (z) of the superconducting structure.
Such a superconducting structure is known from DE 10 2009 028 413 A1.
Superconductors are used to carry electric currents, typically with a high current strength, and may be included in different applications, such as current transfer lines or magnetic coils.
Superconductors may, at a temperature below the so called critical temperature Tc, carry the electric current at practically no ohmic losses. In order to achieve said low temperature, the conductor is typically cooled, for example with liquefied gases such as liquid helium. Further, to have a superconducting state, it is also necessary to stay below a critical current density and below a critical magnetic field with the conductor.
When using high temperature superconductor (HTS) materials, e.g. yttrium barium copper oxide (YBCO) material, higher temperatures, current densities and magnetic fields become accessible. Since known HTS materials are brittle, HTS material is typically used as a film (or coating) on a normally-conducting or insulating substrate. Currently, most applications of HTS materials are based on coated conductor tapes, wherein the tapes provide some mechanical flexibility to the coated conductor.
The superconducting film deposited on a substrate tape is relatively thin, and limits the absolute current strength that may be transported through the coated conductor. In order to increase the absolute current strength that may be transported, it is known to electrically connect a plurality of coated conductor tapes in parallel.
DE 10 2009 028 413 A1 discloses a HTS current lead device for connecting a superconducting current consumer with a current supply point, with the device comprising several HTS tapes arranged on a support in parallel and spaced apart from each other. Note that this structure is rather large scaled, and the support makes the structure unflexible.
U.S. Pat. No. 7,774,035 B2 discloses superconducting articles wherein two superconductor tapes are bonded together, with the superconducting films facing away from each other.
In these superconducting structures, a coated conductor may easily be overloaded and lose its superconducting state (“quench”), what in turn often leads to a quench of the complete superconducting structure. Furthermore, the critical or quench current threshold is not sufficient.
It is the object of the invention to provide more stable superconducting structure with which high electric current strengths may be transported.